Because your body doesn't adapt, you just suddenly took strenuous exercise, so a lot of protein in your body didn't burn completely, so you produced something called lactic acid. Your whole body aches because lactic acid is doing strange things, so your body should absorb it slowly, or you can do light exercise the next day to speed up your body's absorption, and you will feel much better on the third day.

Another reason for fatigue is that your nutrition has not kept up. After exercise, you should add a lot of protein and energy, and your body will recover quickly. Fitness is three-point exercise and seven-point nutrition. . .

Please adopt it. . . .